Urinary stress incontinence is a medical condition in which sudden stress placed on a patient's bladder causes urinary incontinence. Activities such as laughing, sneezing, and lifting heavy objects frequently cause stress incontinence in susceptible patients. According to the National Institutes of Health, about 50% of all women have occasional urinary incontinence, and as many as 10% have frequent incontinence. Nearly 20% of women over age 75 experience daily urinary incontinence. Stress incontinence may occur as a result of weakened pelvic muscles that support the bladder and urethra, or because of malfunction of the urethral sphincter. Stress incontinence is often seen in women who have had multiple pregnancies and vaginal childbirths, or who have pelvic prolapse, with cystocele, cystourethrocele, or rectocele (protrusion of the bladder, urethra, or rectal wall into the vaginal space). Risk factors for stress incontinence include female sex, advancing age, childbirth, smoking, and obesity.
Urge incontinence involves a strong, sudden need to urinate, immediately followed by a bladder contraction, resulting in an involuntary loss of urine. The bladder's ability to fill and store urine requires a functional sphincter (muscle controlling output) and a stable bladder wall muscle (detrusor). Undesired bladder muscle contraction may occur as the result of a break in a neurological pathway from the brain to the bladder. It can also occur if the bladder is irritated and the normal neurological impulses to inhibit urination are insufficient to keep the bladder relaxed as it fills. Urge incontinence may result from neurological injuries (such as spinal cord injury or stroke), neurological diseases (such as multiple sclerosis), infection, bladder cancer, bladder stones, bladder inflammation, or bladder outlet obstruction.
Although urge incontinence may occur in anyone at any age, it is more common in women and the elderly. It is second only to stress incontinence as the most common cause of urinary incontinence (involuntary loss of urine), and it is common for people with stress incontinence to also have urge incontinence.
In the urology field, needles, suture passers and ligature carriers are utilized in a variety of procedures, many of which are designed to treat incontinence. A pubovaginal sling procedure is a surgical method involving the placement of a sling to stabilize or support the bladder neck or urethra. There are a variety of different sling procedures. Descriptions of different sling procedures are disclosed in U.S. Pat. Nos. 5,112,344 to Petros et al., 5,611,515 to Benderev et al., 5,842,478 to Benderev et al., 5,860,425 to Benderev et al., 5,899,909 to Claren et al., 6,039,686 to Kovac, 6,042,534 to Gellman et al., and 6,110,101 to Tihon et al., which are incorporated herein by reference and are described hereinbelow.
Some pubovaginal sling procedures extend a sling from the rectus fascia in the abdominal region, to a position below the urethra, and back again to the rectus fascia. The Tension-free Vaginal Tape (TVT) procedure (Ethicon, N.J.) utilizes a Prolene™ nonabsorbable, polypropylene mesh. Additional sling procedures are disclosed in US Patent Application Publication 2001/0018549A1 to Scetbon, and PCT Patent Publications WO 02/39890 to Ulmsten et al. and WO 02/069781 to Ulmsten et al., which are incorporated herein by reference and are described hereinbelow. Other examples of a mesh sling used for treating incontinence include the In-Fast™ and InVance™mesh sling (American Medical Systems, Inc., Minnetonka, Minn.), which are the subject of various patents and applications. In general, these systems use bone anchors to affix the mesh sling to the pubic bone in a manner that compresses the urethra.
The BioArc™ SP Sling System and the BioArc TO Subfascial Hammock (American Medical Systems) treat female stress incontinence with a minimally invasive procedure using either a suprapubic (BioArc SP) or a transobturator (BioArc TO) approach. The BioArc utilizes a polypropylene mesh for fixation and a biologic graft material for suburethral support. Tensioning and loosening sutures maintain mesh integrity during placement and allow for intra-operative tensioning refinement without distorting the biologic graft material.
Both the BioArc SP and BioArc TO have two pieces of precut polypropylene mesh with attached clamps. The mesh and clamps are designed to facilitate the attachment of the surgeon's choice of graft materials. Tensioning and loosening sutures allow for intra-operative tension adjustment without mesh or biologic distortion. The BioArc is minimally invasive, and patients typically experience immediate continence following surgery.
The Monarc™ Subfascial Hammock™ (American Medical Systems) is a minimally invasive treatment option for female patients suffering from stress incontinence. The Monarc treats stress incontinence by supporting the urethra during abdominal stress events, such as sneezing, coughing or laughing. Monarc's outside-to-in transobturator approach avoids the retropubic space. A knitted, polypropylene mesh creates a hammock-shaped midurethral sling, and helps to maintain continence by supporting the midurethra during times of increased abdominal pressure. Knitted, polypropylene Type I mesh offers tissue fixation without suturing and large pores to facilitate tissue integration. The tensioning suture maintains mesh integrity during placement and allows for intra- and immediate post-operative tensioning, while reducing sling deformation. After the procedure, most patients experience immediate continence.
The SPARC™ Self-Fixating Sling System (American Medical Systems) utilizes a suprapubic approach to treat female stress incontinence due to urethral hypermobility and/or intrinsic sphincter deficiency (ISD). It utilizes a self-fixating sling with a resorbable tensioning suture that allows for intra-operative tension refinement without mesh distortion, as well as immediate post-operative adjustment prior to tissue ingrowth. The sling supports the urethra during increased abdominal pressure (e.g., sneezing, coughing or laughing). Large pores of the mesh promote tissue integration for healing. The 1.1×50 cm polypropylene mesh sling is covered with a plastic sheath, and has locking connectors attached. SPARC's resorbable tensioning suture maintains mesh integrity during placement and allows for intra- and immediate post-operative tensioning, while reducing sling deformation. Patients typically experience immediate continence following the implantation procedure.
The In-Fast™ Ultra Transvaginal Sling (American Medical Systems) is a minimally invasive treatment for female stress incontinence. To place a sling, the In-Fast Ultra inserter is used to drive two small titanium bone screws into the posterior aspect of the pubic bone. Each screw has a suture attached that facilitates attachment to a biologic graft or synthetic mesh that is placed under the urethra, thus restoring lost pubocervical support. The graft or mesh provides support for the urethra to restore continence. The In-Fast produces immediate continence in most cases.
U.S. Pat. Nos. 6,354,991 and 6,896,651 to Gross et al., which are incorporated herein by reference, describe a device and method for treatment of urinary stress incontinence. At least one electrode is implanted in a pelvic muscle of a patient. A control unit receives signals indicative of abdominal stress in the patient and responsive thereto applies an electrical waveform to the electrode which stimulates the muscle to contract, so as to inhibit involuntary urine flow through the patient's urethra due to the stress.
U.S. Pat. No. 6,652,449 to Gross et al., which is incorporated herein by reference, describes a device for treatment of a patient's urinary incontinence, including a sensor, which generates a signal responsive to a physiological characteristic indicative of a likelihood of incontinence. A control unit receives the signal from the sensor. At least one electrode is preferably implanted in the patient. The electrode is coupled to cause contraction of the pelvic muscle of the patient responsive to application of electrical energy to the electrode. Responsive to the signal, the control unit applies an electrical waveform to the electrode, so as to inhibit the incontinence.
U.S. Pat. No. 6,862,480 to Cohen et al., which is incorporated herein by reference, describes a device for treating a medical condition. A surgical procedure for implanting the device is also disclosed. The device includes a sensor, which is adapted to generate a signal responsive to a state of a patient, and at least one electrode, which is adapted to be coupled to a pelvic site of the patient. A control unit is adapted to receive the signal, to analyze the signal so as to distinguish between an imminent stress incontinence event and an imminent urge event, and, responsive to analyzing the signal, to apply an electrical waveform to the at least one electrode. In various configurations, the device may be used alternatively or additionally to treat fecal incontinence, interstitial cystitis, chronic pelvic pain, or urine retention.
U.S. Pat. No. 6,941,171 to Mann et al., which is incorporated herein by reference, describes a method and system for treatment of incontinence, urgency, frequency, and/or pelvic pain. The method includes implantation of electrodes on a lead or the discharge portion of a catheter adjacent the perineal nerve(s) or tissue(s) to be stimulated. Stimulation pulses, either electrical or drug infusion pulses, are supplied by a stimulator implanted remotely, and through the lead or catheter, which is tunneled subcutaneously between the stimulator and stimulation site. For instance, the system and method may reduce or eliminate the incidence of unintentional episodes of bladder emptying by stimulating nerve pathways that diminish involuntary bladder contractions, improve closure of the bladder outlet, and/or improve the long-term health of the urinary system by increasing bladder capacity and period between emptying. Moreover, the system and method may allow a patient to be taught to receive one or more patterns of neural stimulation that can be prescribed by a physician and administered without continuous oversight by a clinical practitioner.
U.S. Pat. No. 6,135,945 to Sultan, which is incorporated herein by reference, describes apparatus for preventing uncontrolled discharge of urinary fluid from a patient urethra. The apparatus includes a pressure sensor operable for sensing intra-abdominal pressure when implanted in a patient and operable for generating a pressure signal in response to the sensed pressure. An actuating device is operably coupled to the pressure sensor and is responsive for generating an electrical signal in response to the pressure signal. A controller is operably coupled to the actuating device and configured for engaging the urethra to selectively compress the urethra and prevent incontinence. The controller includes a plate adapted to be positioned on one side of the urethra and an element adapted to be positioned on another side of the urethra, and is operable for varying the distance between the element and the plate in response to the electrical signal to compress the urethra therebetween so that incontinence is prevented when intra-abdominal pressure is experienced by a patient. In an embodiment, the controller is simply an electrode placed inside the wall of the urethral sphincter to enhance its contraction and tone during the increase in the intra-abdominal pressure.
In an embodiment described in the '945 patent, apparatus for preventing uncontrolled discharge of urinary fluid from a patient urethra includes (a) a pressure sensor operable for sensing intra-abdominal pressure when implanted in a patient and operable for generating a pressure signal in response to the sensed pressure; (b) an actuating device operably coupled to the pressure sensor, the actuating device responsive for generating an electrical signal in response to the pressure signal; and (c) a controller operably coupled to the actuating device and configured for engaging the urethra to selectively compress the urethra and prevent incontinence. The controller comprises a sling adapted to be positioned on one side of the urethra, a movable metal element coupled to the sling, and an electromagnetic element positioned proximate the metal element, the electromagnetic element creating a magnetic field proximate the metal element in response to the electrical signal for magnetically moving the metal element and thereby directing the sling against the urethra to compress the urethra so that incontinence is prevented when intra-abdominal pressure is experienced by a patient.
U.S. Pat. No. 5,112,344 to Petros et al., which is incorporated herein by reference, describes a method of treating female incontinence comprising looping a filamentary element between the wall of the vagina and the rectus abdominis sheath in the anterior wall of the abdomen whereby it passes to each side of the urethra into the correct spatial relationship to the pubis, allowing the development of scar tissue between the vaginal wall and the rectus abdominis sheath, and removing the filamentary element. A surgical instrument for use with the method comprises a surgical instrument for the application of a filamentary element into the body for the purpose of treating female incontinence, the instrument comprising a tubular shaft having a handle at one end and carried toward its other end a flexible needle element slidably receivable in the shaft and adapted at one end to receive a filamentary element and having an enlarged profiled portion at its other end whereby when the needle element is received in the shaft the other end of the needle element defines a convergent surface of the other end of the shaft and the one end of the needle element is exposed at the one end of the shaft.
U.S. Pat. Nos. 5,611,515, 5,842,478 and 5,860,425 to Benderev et al., which are incorporated herein by reference, describe a surgical treatment of stress urinary incontinence. The described methods include: 1) a technique of probe passage intended to avoid injuring the bladder and to provide a more accurate and reproducible capture of the pubocervical fascia lateral to the bladder neck and urethra, 2) anchor fixation of the suspending sutures to the pubic bone intended to decrease the risk of suture pull through from above and to decrease post-operative pain and 3) a technique intended to simply and reproducibly set a limited tension of the suspending sutures. A description of these methods and results of procedures with some of these methods are disclosed. Drill guides, suture passers, suture tensioners, and various related tools and devices for use in the surgical method are also described.
U.S. Pat. No. 6,039,686 to Koval, which is incorporated herein by reference, describes a pubic bone-mounted urethra stabilization and support system and method therefor for the long term cure of recurrent female urinary incontinence. The system comprises a pair of anchors affixed to the posterior/inferior pubic bone, sutures attached to the anchors, and a mesh sling passing behind and about the urethra and the adjacent endopelvic fascia and having ends attached to the anchors by the anchor-mounted sutures. The method includes the steps of accessing the urethra with the endopelvic fascia therebehind and the pubic bone, properly locating and attaching the anchors to the pubic bone, properly locating the sling about the urethra and adjacent endopubic fascia and suturing and tensioning the ends of the sling to the anchors, intending to cause the sling to restore, support and stabilize functional urethral continence anatomy and intending to prevent urethral descent under intraabdominal pressure.
U.S. Pat. No. 6,042,534 to Gellman et al., which is incorporated herein by reference, describes prefabricated urethral suspension slings, methods of making the slings, methods of attaching suture to the slings, kits comprising the slings, and methods of using the slings to treat urinary incontinence. The slings comprise a biocompatible material having an elongate shape adapted for urethral suspension. The material has a central portion extending longitudinally between a first end portion and a second end portion. Each end portion of the sling contains at least one suture receiving site. The suture receiving sites are formed prior to surgery and may be reinforced through a variety of means. Sutures may be attached to the suture receiving sites during the manufacturing process or by the physician prior to or during surgery. Additionally, the end portions of the sling containing the suture receiving sites may be thicker than the central portion of the sling.
U.S. Pat. No. 6,110,101 to Tihon et al., which is incorporated herein by reference, describes a sling for supporting the urethra and neck of the bladder to prevent urinary incontinence. The sling is intended to provide sufficient support to inhibit the unintended flow of urine, yet stretch in a controlled fashion so that the bladder can be voided at appropriate times.
US Patent Application 2001/0018549 to Scetbon, which is incorporated herein by reference, describes a device for treating urinary stress incontinence in women, including a flexible and elongate mechanism including a tape for supporting a urethra and a flat protective sheath enveloping the tape; and a puncturing needle with an active distal end and a proximal end connected to a first end of the flexible and elongate mechanism, wherein the proximal end of the puncturing needle is connected to a first end of the flexible and elongate mechanism by an intermediate traction element, a second end of the flexible and elongate mechanism being free. A method for treating urinary stress incontinence in a woman suffering from urinary stress incontinence is also described, including (a) forming an opening in an anterior vaginal wall; (b) creating, from two small suprapubic incisions formed in the abdominal wall, a right track and a left track from the abdominal skin to the opening formed in the anterior vaginal wall; (c) using a needle and an intermediate traction element to follow one of the tracks and following the other track with at least a needle; (d) verifying by cystoscopy that the paths of the tracks are outside the bladder and the urethra; (e) using a support tape surrounded by a plastic sheath to follow the tracks by passage under an inferior surface of the urethra; (f) adjusting a loop formed by the sheathed tape under the inferior surface of the urethra; (g) removing the sheath by pulling the sheath toward the outside of the woman's body through the small suprapubic incisions; and (h) leaving the tape implanted from the first to the second incision and around the urethra to support the urethra.
U.S. Pat. No. 5,899,909 to Claren et al., which is incorporated herein by reference, describes a surgical instrument and a method for treating female urinary incontinence. The instrument comprises a shank having a handle at one end thereof, and two curved needle-like elements which are connected at one end thereof, each with one end of a tape intended to be implanted into the body. These elements can be connected one at a time with the shank at the other end thereof to form a curved end portion of the shank and are intended to be passed into the body via the vagina, each element being dimensioned to extend from the inside of the vaginal wall over the back of the pubic bone to the outside of the abdominal wall. When practicing the method, the tape is passed into the body via the vagina first at one end and then at the other end, at one side and the other, respectively, of the urethra to form a loop around the urethra, located between the urethra and the vaginal wall. The tape is extended over the pubis and through the abdominal wall and is tightened. Then, the tape ends are cut at the abdominal wall, and the tape is left implanted in the body.
PCT Patent Publication WO 02/39890 to Ulmsten et al., which is incorporated herein by reference, describes a surgical instrument and a method for treating female urinary incontinence. The instrument comprises a handle mechanism and one or two curved needle-like elements which are connected at opposite ends of a length of tape, which is implanted into the body. These elements can be connected one at a time with the handle and are intended to pass into the body via the vagina, each needle-like element being dimensioned to extend from the inside of the vaginal wall, under the pubic bone and to the outside of the abdominal wall. When practicing the method, the tape is passed into the body via the vagina first at one end and then at the other end, at one side and the other, respectively, of the urethra to form a loop around the urethra, located between the urethra and the vaginal wall. The tape is extended under the pubis and through the abdominal wall and adjusted. The tape ends are cut at the abdominal wall, and the tape is left implanted in the body.
PCT Patent Publication WO 02/069781 to Ulmsten et al., which is incorporated herein by reference, describes a surgical instrument and a method for treating female urinary incontinence. A tape or mesh is permanently implanted into the body as a support for the urethra. In one embodiment, portions of the tape comprise tissue growth factors and adhesive bonding means for attaching portions of the tape to the pubic bone. In a further embodiment, portions of the tape comprise attachment means for fastening portions of the tape to fascia within the pelvic cavity. In both embodiments, the tape is implanted with a single incision through the vaginal wall.
U.S. Pat. No. 6,652,450 to Neisz et al., which is incorporated herein by reference, describes an implantable article and method of use to treat urological disorders. A biocompatible device includes a sling assembly intended to be minimally invasive and provide sufficient support to the target site. In addition, the configuration of the sling assembly is intended to allow the position of the sling to be permanently changed during and/or after implantation.
U.S. Pat. No. 6,612,977 to Staskin et al., which is incorporated herein by reference, describes an apparatus and method of use to treat urological disorders. A biocompatible device includes a handle, needle, dilator and sling assembly intended to be minimally invasive and provide sufficient support to the target site. In addition, the configuration of the sling assembly is intended to allow the sling to be adjusted during and/or after implantation.
U.S. Pat. No. 6,802,807 to Anderson et al., which is incorporated herein by reference, describes an apparatus and method of use to treat urological disorders. The device is a repositionable handle for an arcuate needle intended to be minimally invasive. The device is for use with a sling assembly that allows a sling to be controllably implanted in a position.
U.S. Pat. No. 6,911,003, US Patent Application Publication 2003/0171644 and US Patent Application Publication 2005/0143618 to Anderson et al., which are incorporated herein by reference, describe surgical articles, implants and components suitable for a transobturator surgical procedure.
US Patent Application Publication 2005/0245787 to Cox et al., which is incorporated herein by reference, describes a method of treating pelvic organ prolapse. The method generally includes the steps of establishing a first pathway between the external perirectal region of the patient to the region of the ischial spine in tissue on one side of the prolapsed organ, followed by establishing a second pathway in tissue on the contralateral side of the prolapsed organ. A support member, which includes a central support portion and two end portions, is described as being positioned in a position to reposition the prolapsed organ in the organ's anatomically correct location. The end portions of the support member are described as being introduced through the respective tissue pathways, followed by adjustment of the end portions so that the support member is located in a therapeutic relationship to the prolapsed organ that is to be supported. An apparatus and kit for the treatment is further described.
US Patent Application 2005/0250977 to Montpetit et al., which is incorporated herein by reference, describes a method for cystocele repair comprising the steps of: establishing four pathways in tissue around a bladder of a patient, introducing a strap into each of the pathways, and positioning beneath the bladder of the patient a support member having each strap connected thereto such that the bladder of the patient is supported by the support member and a bulge of the bladder into a vagina of the patient is reduced.
The following patents and published patent applications are incorporated herein by reference:
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